Synthetic desalination genetic circuit in plants

Abstract

The present disclosure provides compositions and methods for generating plants that can grow in saline conditions, or remove a salt or other impurity from water, for example plants that can remove sodium chloride from salt or sea water, and plants that can produce purified water from salt or sea water.

1 . A transgenic plant genetically engineered to produce purified water, comprising:
 a) genetically encoded physical barrier components;   b) genetically encoded water filtering and transport components; and   c) genetically encoded water retention and pumping components,   wherein said plant produces purified water when grown in water containing an impurity, and wherein at least one of said components is exogenously provided to said plant.   
     
     
         2 . The plant of  claim 1 , wherein said genetically encoded physical barrier components comprise suberin and a Casparian Strip. 
     
     
         3 . The plant of  claim 2 , wherein the suberin is encoded by a MYB41 gene that has been mutated to encode an aspartate residue at amino acid 251 or the Casparian strip is encoded by a MYB36 gene. 
     
     
         4 . The plant of  claim 3 , wherein:
 a) the MYB41 gene is from a dicot plant;   b) the MYB41 gene is from  Arabidopsis thaliana, Eutrema salsugineum , or  Brassica napus;      c) the MYB41 gene is from a monocot plant;   d) the MYB36 gene is from a dicot plant;   e) the MYB36 gene is from  Arabidopsis thaliana, Eutrema salsugineum , or  Brassica napus ; or   f) the MYB36 gene is from a monocot plant.   
     
     
         5 .- 10 . (canceled) 
     
     
         11 . The plant of  claim 1 , wherein said genetically encoded water filtering and transport components comprise an aquaporin. 
     
     
         12 . The plant of  claim 11 , wherein:
 a) said aquaporin is a plasma membrane intrinsic protein or a tonoplast intrinsic membrane protein;   b) said genetically encoded water filtering components comprise a plurality of distinct aquaporins; or   c) said genetically encoded water filtering components comprise a plasma membrane intrinsic protein and a tonoplast intrinsic membrane protein.   
     
     
         13 .- 14 . (canceled) 
     
     
         15 . The plant of  claim 12 , wherein:
 a) said plasma membrane intrinsic protein is from a dicot plant;   b) the plasma membrane intrinsic protein is from  Avicennia officinalis  or  Bruguiera gymnorrhiza;      c) the plasma membrane intrinsic protein is encoded by the is AoPIP1.2 gene from  Avicennia officinalis  or BgPIP2 from  Bruguiera gymnorrhiza;      d) the tonoplast intrinsic membrane protein gene is from a dicot plant;   e) the tonoplast intrinsic membrane protein gene is from  Eutrema salsugineum ; or   f) the tonoplast intrinsic membrane protein gene is TsTIP1.2 from  Eutrema salsugineum.      
     
     
         16 .- 20 . (canceled) 
     
     
         21 . The plant of  claim 1 , wherein the genetically encoded physical barrier components and the genetically encoded water filtering and transport components are expressed by a root epidermal promoter. 
     
     
         22 . The plant of  claim 21 , wherein:
 a) the root epidermal promoter is from a dicot plant;   b) the root epidermal promoter is from  Arabidopsis thaliana;      c) the root epidermal promoter is an ABC transporter promoter, a CLAVATA3/ESR-related 14 promoter, or an iron regulated transporter promoter from  Arabidopsis thaliana;      d) the root epidermal promoter is from a monocot plant;   e) the root epidermal promoter is from a rice plant;   f) the root epidermal promoter is an Os02g51110 or an Os03g01700 promoter; or   g) the root epidermal promoter is a synthetic promoter.   
     
     
         23 .- 28 . (canceled) 
     
     
         29 . The plant of  claim 1 , wherein the genetically encoded water retention and pumping components comprise a mannitol biosynthesis protein and a mannitol transport protein. 
     
     
         30 . The plant of  claim 29 , wherein the mannitol biosynthesis protein is encoded by a mannose-6-phosphate reductase gene or the mannitol transport protein is encoded by a mannitol transporter gene. 
     
     
         31 . The plant of  claim 30 , wherein:
 a) the mannose-6-phosphate reductase gene is from a dicot plant;   b) the mannose-6-phosphate reductase gene is from  Apium graveolens;      c) the mannose-6-phosphate reductase gene is from  Apium graveolens  and has been codon optimized for expression in the plant;   d) the mannitol transporter gene is from a dicot plant;   e) the mannitol transporter gene is from  Apium graveolens ; or   f) the mannitol transporter gene is from  Apium graveolens  and has been codon optimized for expression in the plant.   
     
     
         32 .- 37 . (canceled) 
     
     
         38 . The plant of  claim 1 , wherein the genetically encoded water retention and pumping components are expressed by a xylem parenchyma-specific promoter. 
     
     
         39 . The plant of  claim 38 , wherein:
 a) the xylem parenchyma-specific promoter is from a dicot plant;   b) the xylem parenchyma-specific promoter is from  Arabidopsis thaliana ; or   c) the xylem parenchyma-specific promoter is an XCP1 promoter or a CESA7 promoter from  Arabidopsis thaliana.      
     
     
         40 .- 41 . (canceled) 
     
     
         42 . The plant of  claim 1 , wherein:
 a) the plant is a monocot plant;   b) the plant is a rice, wheat, barley, oats, rye, sorghum or maize plant;   c) the plant is a rice plant;   d) the plant is a dicot plant; or   e) the plant is a soybean, alfalfa, sunflower, cotton, canola, sugar beet, sweet potato, tomato, strawberry, tobacco, banana, grape, cucurbits, pepper, beach plum, wax myrtle, mesquite, salt cedar, crossvine, withe vine, acacia, or laurel fig plant.   
     
     
         43 .- 46 . (canceled) 
     
     
         47 . The plant of  claim 1 , wherein said plant produces purified water when grown in salt or sea water. 
     
     
         48 . A plant part from the plant of  claim 1 . 
     
     
         49 . The plant part of  claim 48 , wherein the plant part is a cell, meristem, root, leaf, node, pistil, anther, flower, seed, embryo, stalk or petiole. 
     
     
         50 . A method of producing purified water from salt or sea water, comprising growing the plant of  claim 1  in salt of sea water and collecting the purified water produced by the plant. 
     
     
         51 . A nucleic acid construct, comprising:
 a) genetically encoded physical barrier components;   b) genetically encoded water filtering and transport components; and   c) genetically encoded water retention and pumping components.   
     
     
         52 . The construct of  claim 51 , wherein:
 a) components a) through c) are separately comprised in a plurality of nucleic acid vectors;   b) components a) through c) are comprised in a single vector;   c) any of components a) through c) are operably linked to a termination sequence;   d) all of components a) through c) are operably linked to a termination sequence;   e) any of components a) through c) are operably linked to a transcriptional enhancer sequence; or   f) all of components a) through c) are operably linked to a transcriptional enhancer sequence.   
     
     
         53 .- 57 . (canceled)